Please refer to this discussion setting up WCF to use SSL. This is required for SSO. You also must be at Accelerator Version 6.2.1 or greater.

Make sure that you set the ClientCredentialType to "Windows"

In you system WPF startup project, open the App.xaml.cs.

Override the am_Initialize() method and add the code in bold below. The ap_UserName and ap_Password will be passed to the service and will be used to look up the user in the Accelerator User Table FWUS.  The ap_UserName is being set to the Windows Identity current user.  Refer to this documentation regarding the WindowsIdentity Class. 

The ap_UserName must be a valid Accelerator User with a User Group that has authority to the system. You have the option to set the password or leave it blank.  Whatever you choose, make sure it matches the password in the FWUS table for the Accelerator User.  If you do use the password, then it will need to be the same for all users.

The call to the base.am_Dologin() will run the login code,  You need to also override the method am_ShowLogon and comment out the base call. This will stop the login from showing.

protected override void am_Initialize()
{
    base.am_Initialize();

    AB_DataPropertyController.ap_UserIdentityStore.ap_UserName = System.Security.Principal.WindowsIdentity.GetCurrent().Name;
    AB_DataPropertyController.ap_UserIdentityStore.ap_Password = "";

    base.am_DoLogin();
}

protected override void am_ShowLogon(AB_LogonBase logonWindow, AB_LogonStartUpTabOption startOption)
{
    //  base.am_ShowLogon(logonWindow, startOption);
}